Power operated chuck



Dec. 10, 1940. G. A. HEGHBERG ET AL 2,224,633

POWER OPERATED CHUCK Filed Nov. 27, 1939 3 Sheets-Sheet l GEORGE A. MGHBERG 19542212) 15 S1: OAN

Dec. 10, 1940. G. A. HIGHBERG ETAL.

POWER OPERATED CHUCK 3 Sheets-Sheet 2 Filed Nov. 27, 1939 GEORGE A. 1%GHBERG 554/91 2) 5 JL OAN 1940. G. A. HIGHBERG ETAL 2,224,

POWER OPERATED CHUCK Filed Nov. 27, 1939 3 Sheets-Sheet 3 gwue/wtow GEORGE 14.1%GHBERG HARRY 5 SL OAN M4 ma /0@ //0 Patented Dec. 10, 1940 2,224,e3s v rowan OPERATED CHUCK George A. Highberg and Harry E. Sloan, Hartford, I Conn., assignors to The Cushman Chuck Company, Hartford, Conn, a corporation of Connecticut Application November 27, 1939, Serial No. 306,277

13 Claims.

The present invention relates to improved power mechanism for radially moving the jaws of a power driven chuck into or out of engagement with a work piece to be supported thereby.

At present, there is commonly employed two types of mechanism for accomplishing the radial movement of the jaws of a power driven chuck. The first of these is well exemplified by the Van Hamersveld Patent No. 1,816,239 wherein a power wrench is substituted for the usual hand wrench which accompanies a standard type of chuck. As is readily apparent from said patent, the power operating means disclosed thereby merely applies mechanical power to the end of a wrench in place of manual power. The second type is well exemplified by the Hay Patent No. 1,441,803 wherein a gear train is provided directly between a source of driving power and the chuck jaws. As is apparent from the Hay patent, the chuck must be especially designed to include elements of the gear train, and a definite mechanical advantage is thus obtained over a power on hand operated wrench.

The present invention relates to power operated jaw actuating means falling in the second category, and the principal object of the present invention is to provide an improved mechanism of this type.

A still further object is a power operated jaw actuating mechanism utilizing a relatively light driving means therefor, though afiording a high mechanical advantage and whereby fine adjustments of the jaws may be obtained.

A still further object is a mechanism of the above-indicated type which is compact, requires relatively few parts, and is both economical and efiicient inoperation.

Other objects will be in part obvious and in part pointed out more in detail hereinafter.

The invention accordingly consists in the fea-' tures of construction, combination of elements, and arrangement of parts which will be exemplified in the construction hereafter set forth and the scope of the application of which will be indicated in the appended claims. I

In the accompanying drawings:

Figure 1 is an end view of a portion of the headstock of a lathe, looking towards the chuck, embodying the jaw actuating mechanism disclosed herein, with parts thereof in section to more clearly show the structure thereof;

Fig. 2 is a view as seen from the left of Fig. 1, also partly in section to show details of construction thereof;

. Fig. 3 is an enlarged sectional view taken the line 33 of Fig. 1;

Fig. 4 is an enlarged sectional view taken on the line 44 of Fig. 1; v

Fig. 5 is an end view looking towards the chuck, with portions of the chuck broken away to show details of construction; and Fig. 6 is a sectional view of the chuck shown in Fig. 5.

Referring to the drawings, there is shown the 10' headstock ID of a lathe; the headstock having rotatably mounted therein a spindle l2. The spindle I2 is controlled through a clutch whereby it may be connected for operation in reverse directions to a driving means, or entirely dis- 5' connected therefromj the clutch and driving means being omitted as they may be of any wellknown construction. The operation of the spindle clutch is controlled by a lever I4 extending forwardly from the vertical center of the headstock and arranged for pivotal movement in a horizontal plane. The spindle l2 has secured. thereto, as by. bolts IS, a chuck I8; the chuck having thereon a plurality'of gripping jaws 20 adapted to be radially moved towards and from the axis of the chuck, whereby they may engage or be disengaged. from a work piececarried thereby.

' In accordance with the present invention, the radial movement of the chuck jaws is accomplished through a gear train extending from a suitable source of power directly to the jaws I and partially housed by a power or driving unit 22 and partially housed within the chuck l8; theunit 22 being so constructed that it may be moved into and out of cooperative driving relation with the chuck and thus make or interrupt the continuity of the gear train.

More specifically, the driving unit 22 includes a rack guide 24, a gear housing 26, and a motor housing 28 joined together as a unitary structure and in which there is respectively mounteda rack 3t, reduction gearing 32, and a source of power 3 3. As best. seen from Fig. 3, the rack guide 24 is in the form of an inverted rectangular U haV- 5 ing a top plate 36 and downwardly depending legs 38 and 40, and the inner face of each leg has integral therewith an outwardly extending rack supporting way 42. The rack 30 is also of rectangular form, with each side wall thereof grooved to receive a way 42 and thus mount the rack for longitudinal movement within the guide 24. To limit the longitudinal movement of the rack, there is arranged adjacent the ends of the upper surface 44 thereof spaced apart shoulders i beforedirect contact is made between one of the abutment 88 46 (see Fig. 1) adapted to abut against a stop member i8'nonrotatably and removably positioned in a slot 50 cut in the top plate 38 of the rack guide.

The longitudinal movement of the rack 30 within the guide is accomplished by providing the interior of the rack with a threaded bore 52 adapted to receive a rotatable screw 54. For simpilicity and economy in manufacture and assembly, the screw 54 not only constitutes driving means for the rack, but also functions as a part of the reduction gear between the power source and the rack. To accomplish this, the inner end 56 of the screw is receivable in the gear housing 26 and has cut thereon a pair of adjacent annular shoulders 58 and 69; the shoulder 60 being of slightly greater diameter than the shoulder 58. Mounted for freerotation on the shoulder 58 is a ring gear 62; the outer periphery thereof being provided with suitable gear teeth 64, adapted to mesh with teeth of a gear 66 carried by a shaft 68, journalled at its forward end in the gear housing 26. The rear portion of shaft 68 extends through and is journalled in the front plate HI of the motor housing 2-3, and the portion thereof extending into the motor housing has splined thereon a gear I2 meshing directly with a gear I4 mounted for simultaneous rotation on the shaft 16 of the power source, thus establishinga direct drive from the power source to the ring gear'62, In the present instance, the driving source comprises a high torque, high speed, relatively low horsepower motor 18-, and in order to permit the use of such motor, lost motion means are provided to enable it to reach speed before directly driving the screw 54.

11he desired lost motion is obtained by providing ring gear 52' with a circumferential shoulder 8i], having an inner surface 82' overhanging and radially spaced from the annular shoulder 60 of the screw head. The inner surfa e 82 of the ring gear has cut thereon a pair of diametrically opposite teeth or radial abutments (13 adapted to contact a single tooth or extending radially from the shoulder 61! of the screw head. The ring gear 52 is thus capable of free rotation through approximately one hundred and eighty degrees-, depending upon the direction of rotationthereof,

abutments carried thereby and the abutment carried by the. screw head, Thus suii'icient lost motion is obtained to allow the motor not only to come up to speed but to strike a sudden blow and overcome, the inertia of the gear train beyond same. i

To further facilitate ease of operation, the enlarged screw head is journalled in suitable ball bearing races at, 92, and 9.4; the ball bearing races QQ-an-d 9 2,being arranged in suitablegrooves cut in the gear housing 26 and the race 94' being arranged in a suitable groove cut in the end plate I0 of the motor housing.

By thus; obtaining the longitudinal movement of the rack 30 from the rotary movement of the screw 54', a maximum power factor is obtained and the speed of the rack may be so controlled that; extremely fine jaw adjustments. may be obtained;. Moreover, due to the large speed reduction obtained by properly coordinating the threaded, engagement between the screw and the rack, the reduction gearing required between the motor I18; and the screw may be reduced toa Ininimum., The. operation of the motor may bereadily controlled through means conveniently located within reach of the operator; such means being omitted herein as they may be of any desired construction.

Furthermore, by constructing the unit in the manner described, it requires but a minimum number of parts and lends itself to rapid assembly and disassembly. By removal of the stop member 48 from the top plate 36 'of the rack guide and the removal of the end plate Ill of the motor housing, the screw 56 and rack 30 may be readily removed from their respective supports. Because of this, a standard rack guide may be utilized for various sizes of chuck; the required power factor and rate of movement of the rack being obtained by utilizing proper pitch for the screw and threaded bore of the rack.

As previously stated, the gear train within the unit 22 is adapted to cooperate with a gear train within the chuck I8, and this is accomplished by pr viding the lower face of the rack 30 with t eth 95 adap ed to coopera ively en a t peripheral teeth are of an actuator ringflii. The actuator ring 9.5 is part of the gear train housed within the chuck I3, and, as best. seen in Fig. 6, it is mounted for rotat on on. a circumferential should r 98 provided on the chuck body 1.00. The rin 86 is f rther, provided on the radial face HM thereof with a, second set, of peripheral teeth lot, which, teeth are in meshing engagement with a plurality of pinions IE8 The pinions- ID8 are radially disposed and iournalled in the chuck body, and there also meshes therewith the teeth IID of a scroll plate II2-, which plate, upon being rotated, actuates the gripping jaws 20 radially in a well-known manner. The

actuator ring $5, pinions I 08, and scroll plate II2 thus complete an unbroken gear train from the motor I8 to the gripping jaws 20 when the rack 30. is in engagement with the actuator ring.

Because of the compactness of the unit, 22 it can also be mounted directly on the headstock, thus making it within convenient reach. of the operator for moving it into and out of cooperative engagement with the chuck. In order toso mount the unit, there is provided thereon a pair of spaced apart supporting brackets H4? and H6, joined together by a spacer plate H8; the bracket H6 being integrally secured-and preferably cast with the rack guide 24. The brackets I14, and H5 are provided with aligned longitudinal bores adapted to receive a sleeve I20; about which the unit may be pivoted. The sleeve I20 is supported on the headstock bya pair of spaced apart brackets I22 and I24' located rearwardly of the vertical center line of' the chuck and secured to the headstock in any suitable way. As it is essential that the rack 36 be mounted in proper longitudinal relationship with the actuator ring 96, the spacing of the supporting brackets I.I.4'

and II-6 of the unit is such that when the device is assembled" they straddle the sleeve supporting bracket I24; and thus the unit is maintained in proper longitudinal position. The foregoing means for mounting the, unit facilitates assembly thereof in that itzisonlynecessary to align the respective supporting brackets and insertthe sleeve therethrough, and, if repairs are required, by simply removing" the sleeve the entire unit 22' may be readily removed from the machine.

The pivoting of the unit 22' into and out of operative engagement isaccomplished by a manually operated lever I26 arranged for convenient manipulation by the operator: The lever I26 is secured to one arm I28 of abell crank I30, which crank is mounted for pivotal movement about a pivot pin I32 carried by an arm I35 integral with and extending upwardly from the sleeve supporting bracket I24. The other arm I36 of the bell crank I30 is connected to the rack guide 24 through a toggle link I38, which link has its upper and lower ends respectively pivoted to the arm I36 and upper plate 36 of the rack guide. The toggle link I38 is of such length that when lever I26 is in horizontal position, the toggle is just over dead center abutting against a stop I40, and the rack '30 is in meshing engagement with the actuator ring 96. Upon movement of the lever I26 vertically, the toggle will be broken, whereupon unit 22 will be pivoted about the supporting sleeve I20, moving the rack 30 out of engagement with the actuator ring 86 and thus breaking the continuity of the gear train from the motor I8 to the gripping jaws 20.

It is essential that the chuck I8 be held against rotation when the unit is moved into operative position, and to accomplish this, means are provided which are automatically operative to prevent rotation of the chuck simultaneously with the movement of the unit into operating position. This is accomplished by arranging in the leg 40 of the rack guide a rectangular opening in which there is positioned a block I42, the lower face of which defines a gear segment I43 consisting of three teeth adapted to move into and out of meshing engagement with the peripheral teeth I44 of a chuck plate I46 secured to the chuck body by bolts I48. As best seen in Fig. 3 the block I43 is provided with a slot I therein 'through which a pin I41 extends 'for holding same within the rack opening provided therefor. Positioned to either side of the center of the block are elongated openings I49 for receiving a spiral spring ISI for normally urging the block downwardly towards the plate I46. With this construction, when the leg is moved downward and into engagement, if the teeth I43 of the block and the teeth I48 of the chuck holding plate are not in exact alignment, the springs I5I will permit the block to yield until alignment is made and thus damage to the meshing parts is avoided.

The clutch holding means just described further adds to the simplicity of the structure and ease of control thereof. The operator, through the manipulation of the unit control handle I26, thus simultaneously moves the rack 30 into enengagement with the actuator ring 96 and the holding segment I42 into engagement with the holding plate I46. Insasmuch as both the ring and holding plate have teeth disposed around the entire periphery thereof, engagement will be obtained at any point of stoppage of the chuck. Moreover, as the unit 22 is secured in.

position by the toggle I38, a positive engagement of the cooperating holding means is assured.

The unit is further provided with means for interlocking the chuck control lever I4 in neutral position when the unit is in operating position, as well as preventing the movement of the unit to operating position when the lever I4 is out of neutral position. As best seen in Fig. 2, the interlock for accomplishing the above purpose includes a lever I50 integrally secured to the guide rack 24 and extending laterally therefrom toward the lever I4. There is cut adjacent the outer end of the lever I50 2. downwardly facing groove I52 into which the lever I4 may be received. As readily seen from Fig. 2, when the lever I4 is positioned within the groove I52, the unit 22 is in operative position and the lever I4 cannot be moved from its neutral position. Obviously whenever the lever I4 is out of neutral position to either side of the groove I52, as indicated by dotted lines in Fig. 2, it will underlie the lower edge I54 of the lever I50 and thus prevent the unit from being moved into operative position.

Although the operation of the device is readily understandable from the foregoing, it is pointed out here that the .entire control is obtained through the instrumentality of the single unit operating lever I26 and that movement of this lever performs three functionsnamely, it carries the rack 30 into meshing engagement with the actuator ring 96, thus establishing a continuous gear train from the motor I8 to the gripping jaws 20. It carries the gear segment I42 into engagement with the holding plate I46 of the chuck; thus restraining the chuck against rotation, and it carries the lever I50 into position to interlock the clutch operating lever I4 against movement to operative position.

As many changes could be made in the above construction and many apparently widely different embodiments of this invention could be made without departing from the scope thereof, it is intended that all matter contained in the above description or shown in the acompanying drawings shall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the language used in the following claims is intended to cover all of the generic and specific features of the invention herein described and all statements of the scope of the invention which, as a matter of language, might be said to fall therebetween.

We claim as our invention:

In a tool of the character described, a rotatable chuck, work holding jaws movable on said chuck, an exterior toothed gear rotatably mounted on the chuck and operatively connected to the work jaws, a power unit for rotating said chuck gear including a housing, a rack slidably mounted in the housing and engageable with said rotatable gear, power means carried by the housing and operatively connected to the rack, and means supporting the power unit for pivotal movement whereby the rack may be moved into and out of meshing engagement with the rotatable gear.

2. In a tool of the character described, a rotaable chuck, work holding jaws movable on said chuck, an exterior toothed gear rotatably mounted on said chuck and operatively connected to the work jaws, an exterior toothed holding plate fixed to the chuck adjacent the gear, a power unit for rotating said chuck gear including a housing, a rack slidably mounted in the housing and engageable with the rotatable gear, power means carried by the housing and operatively connected to the rack, a rack segment carried by the housing adjacent the rack, and means supporting the power unit for pivotal movement whereby the rack and rack segment will be simultaneously moved into and out of meshin engagement respectively with the rotatable gear and holding plate.

3. In a tool of the character described, a rotaable chuck having a chuck body with peripherally extending exterior teeth, work holding jaws movable on said chuck, an exterior toothed gear rotatably mounted on said chuck and operatively connected to said work jaws, a power unit including a rack segment engageable with said peripheral teeth for non-rotatably holding said chuck and a slidable rack for engagingsaid chuck gear for rotating same to operate said chuck jaws, andmeans for pivoting said power unit into and out of position relative to said chuck.

4. In a tool of thec'haracter. described, a rotatable chuck, work holding jaws movable on said chuck, power means for operating said jaws, a gear train extending between said power means and said jaws and including a meshing drive rack and driven gear and means for moving said rack and gear relative to one another out of meshing engagement to break the continuity of said gear train.

5. In a tool of the character described a rotatable chuck, work holding jaws movable on the chuck, a power unit for operating said chuck mounted for pivotal movement towards and from said chuck, power means carried thereby, a gear train extending from said power means to said chuck and including a drive rack carried by the power unit and a driven gear carried by the chuck, said rack being simultaneously movable with said power unit into and out of engagement with said gear whereby the continuity of said gear train may be made or broken.

6. In a tool of the character described, a rotatable chuck, work holding jaws movable on said chuck, a power unit for moving said jaws, cooperating engageable driving means carried by said power unit and said chuck for operatively connecting said unit to said jaws, and cooperating engageable holding means carried by said unit and said chuck for nonrotatably holding said chuck upon engagement of said cooperating driving means, and means pivotally mounting said unit for movement towards and from said chuck whereby said cooperating means will be simultaneously engaged or disengaged.

'7. In a tool of the character described, a rotatable chuck having work holding jaws, a lever mounted on the tool for starting rotation of the chuck, a power unit pivotally mounted on said tool for movement toward and from said chuck and including drive means engageable with means on said chuck for operating the work holding jaws, holding means engageable. with means on said chuck for nonrotatably holding same, means for engaging said starting lever for locking said lever in neutral position, said drive means, holding means and starting lever engaging means being simultaneously moved into and out of operative position upon pivotal movement of the power unit towards and from the chuck.

8. Chuck jaw operating means comprising a housing having means for pivotally mounting it on a headstock, power means carried in the housing, a rack slidable in the housing and driven by a screw operatively connected to said power means through a lost motion connection.

'9. Chuck jaw operating means comprising a housing having means for pivotally mounting it on a headstock, a high speed high torque motor carried by the housing, a rack slidable in the housingand driven by a screw operatively connected to said motor through a lost motion connection.

10. In a tool of the character described, a rotatable chuck having work engaging means, a rotatable gear mounted on said chuck and operatively connected to said work engaging means, a power unit mounted on said tool for pivotal movement towards and from said chuck and including a rack engageable with said chuck gear and cooperating means carried by said power unit and said chuck and simultaneously operative upon engagement of said rack and gear for non-rotatably holding said chuck.

11. In a tool of the character described, a rotatable chuck having Work engaging means, a gear carried by said chuck and operatively connected to said work engaging means, a second gear fixed to said chuck for simultaneous rotation therewith, a power unit pivotally mounted on said tool for movement towards and from said chuck and including a longitudinally movable rack engageable with said rotatable gear and a plurality of fixed teeth on said unit simultaneously engageable with said fixed gear for non-rotatably holding said chuck.

12. In a tool of the character described, a rotatable chuck having work engaging means, a gear carried by said chuck and operatively connected to said work engaging means, a second gear fixed to said chuck for simultaneous rotation therewith, a power unit pivotally mounted on said tool for movement towards and from said chuck and including a longitudinally movable rack engageable with said rotatable gear and a plurality of fixed teeth on said unit simultaneously engageable with said fixed gear for nonrotatably holding said chuck, a lever mounted on said tool for pivoting said power unit, a toggle connection between said lever and said unit movable past dead center position upon movement of said power unit into operative position whereby said unit will remain in operative position until release of the lever.

13. Chuck jaw operating means comprising a housing having means for pivotally mounting it on a headstock, power means carried in the housing, a rack slidable in the housing, a screw for operating said rack, a driving abutment mounted on said screw, a gear rotatably mounted on said screw and having an abutment engageable with said screw abutment and means operatively connecting said gear to said power means.

GEORGE A. HIGHBERG. HARRY E. SLOAN. 

